Butterfly time!
The
mustard ZNSC was just ready to unmould now, after five days sitting in the mould. Still quite soft, so it was easy to cut, but also somewhat slippery, and I'm not proud of the (absence of) right angles on these bars
.
I again used about the same amounts of pigment for each colour, but the amount of coloured batter was much greater now, so that the colour depth wasn't just as high as in the first run (good to avoid stains from the suds, but also the reason why I decided to not show the two batches next to each other).
My main issue with the
swirl was that the colours spread over the whole width of the mould, so that it looks like curves stripes, rather than blobby like a butterfly body.
This time, I did three things to counteract this: 1. wait for thicker trace, 2. use more coloured/less background batter, and 3. (don't let
@Zing know this) alternating wall pour: after I had poured about half of the coloured batter, I poured yellow from the opposite side of the mould, to push the batter back towards the side along which I had originally poured it. This all worked well, but I overdid no. 2., hence the swirls don't look as nimble and elegant as in the first run.
I like the way how the butterfly
hanger swirl itself came out, especially in the middle cut (large photo, left), where I originally hadn't intended to cut at all (but it was worth it, IMHO! I got an accidental extra band of green at the bottom!). The pattern might have tolerated much more swirling, or maybe a second yellow band amidst the colours; but I'll approach this technique step by step.
For now I'm happy with my butterflies! I do have one bar with opposite side colourations (ventral/dorsal), the others are pretty as well, and I don't have to resort to the trimmings for beautiful swirl patterns.
One weird thing to notice about the “old” soap (75 days in, bottom right photo): look at this
yellow/white! 
When the soap was about half as old as it is now, I had posted how the yellow of the soaps
looked under UV light. Turns out: this UV was prophetic about the really peculiar thingies to happen with the yellow since then. The areas that lightened up under UV light, have now completely lost their yellow colour, also under visible light! Without doubt this is connected to the iron oxide pigments, and their reaction with whatever lends mustard and/or red palm oil its colour. The brown in the new soap is once again iron oxide based (caput mortuum), so the next weeks & months will show how reproducible this is.
. There, I had also an ombré gone wrong with glycerin river side-effects doing things that I hadn't foreseen (those dark, waxy lines between layers are really weird).
(but also no SB cleaning afterwards 
), and very manageable waiting times. I don't know what was different than last time. The only definitely varied ingredient was the castor oil from a new supplier.
I'm aiming for tomorrow evening to spread the butterfly wings, but I can't promise it. Unmoulding would happen a few days into the new year anyway.
